On Computers: Delete never deletes; you need a disk washer for that

Monday

Jan 27, 2014 at 5:15 PMJan 27, 2014 at 5:17 PM

By Jim HillibishMore Content NowWhen you give a used phone, tablet or computer to somebody, it’s not enough to delete all of your data files. The word “deleting” is one of the great misnomers of computing.When you delete a file, all you do is change its entry name on the hard drive. It could be as simple as turning the first bit of the file upside down. That makes the data invisible, but it is still there. There are programs that restore the entry with a mouse click, and the deleted file reappears.Deleting only tells the hard drive that the space is available for new data. Eventually, the space will be overwritten, depending on how much data you generate.If you want to permanently delete a file, you need a program called a disk wipe or a wash. They are the same. These programs write random letters over all deleted files. You’ll have your choice of a single overwrite or a more secure wash to Department of Defense standards, which is seven passes of overwritten letters. Some programs make up to 23 passes for especially sensitive data.You may find disk washers on programs that clean hard drives of useless data, such as the CCleaner (check the tools section). Check your app store for disk washers for hand-held devices. On a well-used, 500-gigabyte drive, the wash could take hours. Adding more overwrites expands the time.If you examine the washed disk with a file-recovery utility such as Recuva, all you’ll see is incomprehensible letters.Some disk washers offer an option that automatically washes every file as it is deleted by you. This slows your system somewhat but is valuable if you handle lots of secure data such as banking and brokerage accounts.ABOUT ENCRYPTINGNote that encryption is different from disk washing. It converts a file to an unreadable code but does not delete it. A key is needed to unlock the encryption. If you need to permanently delete an encrypted file, use a disk washer.MS SUPPORT ENDINGMicrosoft has released dates when its support services, including updates and security fixes, will end for various Windows versions. Mainstream support is provided free with online updates and security fixes. Extended support requires a paid contract and includes mainstream support plus other features.• Windows XPMainstream support expiredEnd of extended support April 8, 2014• Windows VistaMainstream support expiredEnd of extended support April 11, 2017• Windows 7End of mainstream support Jan. 13, 2015End of extended support Jan. 14, 2020• Windows 8End of mainstream support Jan. 9, 2018End of extended support Jan. 10, 2023Jim Hillibish is a columnist at The Repository in Canton, Ohio. Reach him at jim.hillibish@cantonrep.com.